Well packer



P. J. LEHNHARD, JR

WELL PACKER I Filed July 2l, 1959 f2 Sheets-Sheet l f a 1mi., www

ATroRY Patented Apr. 23, 1946 WELL PACKER Philip J. Lehnhard, Jr., Tulsa, Okla., assignor to The Dow Chemical Company, Midland, Mich., a

corporation of Michigan Application July 21, 1939, Serial No. 285,759

15 Claims.

The invention relates to well packers and morev particularly concerns a hydraulically dilatable well packer which is adapted to be seated by a fluid treating agent during the introduction oi said agent into the well, so as to segregate that portion of the well bore above the packer from the portion below the packer during the introduction of the fluid treating agent into either the portion of the well bore below or above the packer.

In the treatment of deep wells, such as oil wells, it is oftentimes desirable to be able to segregate one portion of the well bore from another during'the introduction of a fluid treating agent, for otherwise the fluid treating agent may enter a portion of the formation where it would be wasted, or in some instances actually harmfully affect the production from the well. For example, in the treatment of oil wells drilled into calcareous formations with acid to bring about an increase in the production from the well. it is usually desirable to be able to direct the acid into only the oil producing formation, for otherwise the acid may spend itself ineffectively or penetrate into a water bearing stratum and increase the flow of water so as to ood the well.

It is, therefore, the principal object of the invention to provide a packer wherein the ow of fluid into the well through a conduit on which the packer is mounted will cause the packer to expand and seat against the Well bore or the well casing under a pressure greater than the fluid pressure exterior of the packer.

Another object of the invention is to provide a packer that will readily adapt itself to a bore hole of irregular contour.

Still another object of the invention is to provide an expansible or dilatable well packer which may be readily inflated and deflated to permit subsequent withdrawal from the Well bore.

Other objects and advantages of the invention will appear hereinafter.

In the accompanying drawings, which illus? trate embodiments of the invention, Fig, 1 is a sectional elevational view of one arrangement of the packing device mounted on a tubing string suitably positioned for carrying out a treatment of the formation located below the packer.

Fig. 2 is a sectional elevational view of another arrangement of the packing device positioned for carrying out a treatment of the section of the formation located above the packing device.

Fig. 3 is a sectional elevational view showing two packing devices in combination adapted to seal the well bore both above and below the point of introduction of the fluid agent and having a back pressure valve positioned between the packing elements to contro1 expansion of the packing elements.

Referring to Fig. l of the drawings, the expansible packing element I, made of rubber or the like suitably reinforced if necessary by means of cord-s, wires, or the like, is provided at either end with a bead or rim portion 2 which serves toprevent the expansible element from slipping from engagement with the coupling members 3. Tubular coupling members 3y having outwardly flared and recessed end portions 4, engage either end of the expansible element I interiorly thereof,

while clamping rings 5 provided with recessed portions engage the bead of the expansible element and press against the outer surfaces of the end portions of the expansible element I, as clamping collars 6, threaded upon the tubular members 3, are screwed down upon the clamping rings 5. The beaded end portion of the expansible element I engaging the recesses in the 'flared ends 4 of the coupling members 3 and clamping rings 5 is held securely against slipping as pressure is applied to dilate the packing element. A conventional collar or coupling 'I connects the upper tubular member to a sleeve 8 which is provided with projecting lugs 9. The lugs 9 engage J-slots III in a second sleeve II, which ts over and is adapted to turn on sleeve 9 in sealing relation, permitting ports I2, located in either sleeve to register as the outer sleeve is turned in the J-slots I0, or to be sealed from each other as the outer sleeve is rotated about the inner sleeve. Sleeve II is in turn connected by means of a coupling or collar I3 to a conventional tubing string I4, which serves as a means whereby the packing device may be lowered to the desired position in the well bore, and as a conduit through which the introduction of fluid into the well bore may be brought about. A back presure valve assembly is shown attached to the lowertubular member 3 below the packing element, and consists of a body member I5 which is provided with a seat I6 and ports I1, through which uid may pass from the interior of the packer into the Well bore as the valve is caused to open. A plug member I8 threadedly engages the body portion of the valve assembly and is provided with a well I9 in which the valve stem 20 slides as pressure applied interiorly of the packer overcomes the pressure of the spring 2| acting to force the poppet valve into sealing relationship with the valve seat I6. A reinforcing member 22, in this instance a section of pipe provided with an opening or port 23 through which fluid may flow into the expansible portion of the packer, is connected at either end interiorly of the coupling members 3 and `serves to prevent excessive elongation of the expansible element as the packing device is lowered into or raised from the well. This reinforcing element is not absolutely essential and in those instances where the expansible packing element is suitably reinforced strongly as by means of wire or cord, the additional reinforcing element may be eliminated from the structure.

4In the view shown in Fig. 2, which illustrates the packing device arranged for the introduction of the fluid agent into the formation at a point above the packer, the lower of the tubular members 3 is capped oi by means; of cap 2| to prevent the flow of fluid out the lower end of the packer. The back pressure valve assembly is shown attached to the sleeve 8 a short distance above the packing element as by means of weld 25. The valve assembly consists oi a ported body member 26 having a well 21 in which the valve stem 28 slides as pressure applied interiorly of the packer overcomes the pressure of spring 29 acting to force the valve into sealing relationship against the ported seat 30 provided in sleeve 8.

In the view illustrated in Fig. 3 two packing devices similar to the one described in Fig. 2 are separated from each other at any convenient distance by a tubular element 3|. The tubular element is connected at either end to the packing elements I by means of identical coupling members 'I which threadedly engage the tubular element 3| and the threaded ends of the coupling members 3. The back pressure valve assembly is identical to that illustrated and described in Fig. 2 and is shown attached to the tubular member 3| at a point between the packing elements as by means of weld 25. The valve assembly consists of the ported body member 26 having a well 21 in which the valve stem 28 slides as pressure applied interiorly of the packing elements overcomes the pressure of the spring 29 acting to force the valve into sealing relationship against the ported seat 30 provided in element 3l. Above the top packing element a conventional coupling member 'I threadedly engages the flared coupling member 3 and the tubular element 8. The tubular element 8 is provided with lug members 9 which engage J-slots I9 in a seeond sleeve I I in the manner heretofore described in connection with Fig. 1.

The operation of the well packer is best described in connection with a treatment of a well employing the Packer to introduce a fluid treating agent into the portion of the formation at a point below the packer with the arrangement illustrated in Fig. 1. With the lugs 9 engaging the J-slots I in sleeve II so that fluid is prevented from escaping through ports I2, the packing device, assembled as shown, is lowered into the well to the point where it is desired to segregate one portion of the well bore from another during the introduction of the fluid treating agent. The fluid treating agent is then started into the well through the tubing, and, as pressure ls applied to force the fluid from the tubing through the packer against the pressure exerted by the spring loaded valve, the packing element is caused to dilate and seat at a pressure which is equivalent to the pressure required to depress the spring loaded valve. As the introduction of uid is continued under application of sufficient pressure,

the valve 20 opens and. allows the fluid to escape through portsl I1 into the well bore. Thus, at all times during the introduction of the fluid treating agent, the pressure in the interior of the packer is greater than the pressure in the well bore in an amount equal to the pressure required to depress the spring in the back pressure valve. This maintains the packer in a seated position at all times, under a pressure equal to that required to open the valve against the pressure of the spring. By selecting a spring of proper tension, the packer can thus be seated under any desired pressure, and this pressure is maintained by the action of the valve which closes in case the pressure on the interior of the packer tends to drop below that required to depress the spring, thus producing a highly effective continuous seal by the packer during the introduction of the treating fluid.

In those instances wherein it is desired to seal off the bottom portion of the well during the introduction of fluid agentinto a section of the formation located higher up in the well bore, the packing device arranged as shown in Fig. 2 may be employed.

If desired, two or more hydraulic packers may be used in combination wherein it is desired to seal the well bore both above and below the point of introduction of the fluid agent. In such cases, the back pressure valve assembly or other similar means controlling the expansion of the packing elements is positioned between the packers in such a manner as to allow fluid entry from the tubing into the well bore at any desired point between the packers.

The operation of the packers combined in the manner shown in Fig. 3 is very similar to that described in connection with the operation of the single packing element. The packing assembly assembled asshown is lowered into 'the well at the point where it is desired to segregate a portion of the Well bore between the packers during the introduction of the fluid treating agent. The distance between the packing elements may, of course, be any desired distance depending on the extent of the formation to be treated and may, of course, be varied by varying the length of the tubular element 3I. Fluid treating agent is then started into the well through the tube I4 while lugs 9 engage J-slots Ill in sleeve II so that ports I2 pri vided in sleeves 8 and II do not register, thereby preventing escape of uid above the packers. As pressure is applied to force the fluid from the tubing out through the back pressure valve assembly both packing elements are caused to expand and seat at a pressure which ls equivalent to the pressure required to depress the spring loaded valve. Thus at all times during the introduction of fluid treating agent the pressure in the interior of both packers is greater than the pressure in the well bore by an amount equal to the pressure required to depress the spring in the back pressure valve. This maintains both packers in a seated position at all times during the introduction of fluid treating agent.

After the desired quantity of fluid agent has been introduced, the packing element may be deflated by lowering the tubing and turning it so as to bring the ports I 2, carried by tube 8 and sleeve I9, into registering relation, whereby the fluid pressure inside the tube 9 equalizes with that in the Well bore, causing the packing element to collapse. Thereafter the packer assembly may be withdrawn fromthe well. If desired, the treatmounted on the tubing adapted to seal the an nular space between the well tubing and the well bore, the interior of said packing element being in communication with the well tubing, a spring loaded valve associated with the packing element adapted to maintain a higher pressure interiorly of the packer than exteriorly thereof as fluid .is

forced from the well tubing through said valve" into the well bore, and means located above the packing element adapted to equalize the pressure interiorly and exteriorly of the packing element.

Cil'

2. In a well packer, the combination of, a well tubing, a ported sleeve member depending from the well tubing, a second ported sleeve member adapted to rotate upon the first sleeve member in sealing relation to permit the ports to register, a dilatable packing element associated with the second-mentioned sleeve member below the afore. mentioned parts and adapted to seal the annular space between the well tubing and the well bore, and a spring loaded valve in communication with the packing element adapted to maintain a higher pressure interiorly of the packer than exteriorly thereof as fluid is forced through the valve from the well tubing into the well bore.

3. Apparatus adapted for use in holes in th'e earth, to force cement slurry or other sealing fluid into earth formations, including a tubular member adapted to be lowered into a hole for delivering sealing fluid into the same, two packers mounted in spaced relation on said tubular member, each of said packers being designed to expand and contact the wall of the hole and effect a seal therewith under the influence of fluid pressure exerted internally thereof, means providing an outlet for said tubular member between said packers, valve means controlling the flow of fluid from said tubular member through said outlet means and means for closing said valve except upon the existence of a predetermined excess of fluid pressure on the inside of said packers over the fluid pressure on the outside thereof, the arrangement being such as to prevent the discharge of sealing fluid from said tubular member through said outlet means except when said packers are effecting a seal with the wall of the hole.

4. Apparatus adapted for use in holes in the earth, to force cement slurry or other sealing fluid into earth formations, including a tubular member adapted to be lowered into a hole for delivering sealing fluid into the same, two packers mounted in spaced relation on said tubular member, each of said packers being designed to expand and contact the wall of the hole and effect a seal therewith under the influence of fluid pressure exerted internally thereof, means providing an outlet for said tubular member between said packers, valve means controlling the flow of fluid from said tubular member through said outlet means and a spring exerting force upon said valve tending to keep the same closed, said spring serving to bias or load said valve and prevent the opening of the same except upon the existence of a predetermined excess of fluid pressure on the inside of said packers over the fluid pressure on the outside thereof, the arrangement being such as to prevent the discharge of sealing fluid from said tubular member through said outlet means except when said packers are effecting a seal with the wall of the hole.

5. Apparatus adapted for use in holes in the earth, to force cement slurry or other sealing fluid into earth formations, including a tubular member adapted to be lowered into a hole for delivering sealing uid into the same, a packer mounted on said tubular member, said packer being designed to expand and contact the wall of the hole and effect a seal therewith under the influence of fluid pressure exerted internally thereof, means providing an outlet for said tubular member adjacent said packer, valve means controlling the flow of fluid from said tubular member through said outlet means and means for closing said valve except upon the existence of a predetermined excess of fluid pressure on the inside of said packer over the fluid pressure on the outside thereof, the arrangement being such as to prevent the discharge of sealing fluid from said tubular member through said outlet means except when said packer is eiecting a seal with the wall of the flow of fluid from said tubular member through said outlet means and a spring exerting force upon said valve tending to keep the same closed, said spring serving to bias or load said valve and prevent the opening of the same except upon the existence of a predetermined excess of fluid pressure on the inside of said packer over the fluid pressure on the outside thereof, the arrangement being such as to prevent the discharge of sealing fluid from said tubular member through said outlet means except when said packer is effecting a seal with the wall of a hole.

'1. Apparatus for cementing cased or uncased holes in the earth, including a conduit for conveying cement into the hole and having an outlet near the lower end thereof, a pair of hydraulically expansible packers mounted on said conduit, one on each side of the outlet thereof, a valve for controlling the discharge of cement through said outlet and means for holding said valve closed except when said packers are set to effect seals with the walls of the hole.

8. Apparatus for cementing cased or uncased holes in the earth, including a conduit for conveying cement into the hole and having an outlet near the lower end thereof, a pair of hydraulically expansible packers mounted on said conduit, one on each side of the outlet thereof, a valve for controlling the discharge of cement through said outlet and meansy for holding said valve closed except when said packers are set to effect seals with the walls of the hole, said last mentioned means including a spring for loading said valve and for preventing the opening of the same until a predetermined pressure is built up within said packers.

9. Apparatus for cementing cased or uncased holes in the earth, including a conduit ior conveying cement into the hole and having an outlet s near the lower end thereof, a hydraulically ex pansible packer mounted on said conduit near said outlet, a valve for controlling the discharge of cement through said outlet and means for holding said valve closed except when said packer is set to eiect'a seal with' the wall of the hole.

10. Apparatus for cementing cased or uncased holes in the earth including a conduit for conveying cement into the hole, said conduit having an outlet near the lower end thereof, a circulating sub incorporated in said conduit above saidoutlet, a pair of hydraulically expansible packers mounted on said conduit, one between said cir.. culating sub and said outlet and the other below said outlet, a valve for controlling the discharge of cement through' said outlet. and :means for holding said valve closed except whensaid packers are set to eil'ect seals with-the walls ofthe hole.

11. Apparatus adapted for cementing wells having casing with a perforated section therein, said apparatus includingv a conduit for conveying cement into the well and having an outlet adapted to discharge the cement at a pointfin the well adjacent the perforations in the casing, a pair of hydraulically expansible packers mounted on said conduit in spaced relation and adapted, when expanded, to effect a seal with the casing above and below the perforations therein, a valve for controlling the discharge of cement through said outlet and means for holding said valve closed except when said packers are set to effect seals with the `casing.

l2. A treating tool for wells including a body, a

pair of spaced packers thereon, a discharge section between said packers, an operating pipe to manipulate aid tool and to supply liquid under pressure to be discharged into the well from said section, and means operable so that the pressure liquid will rst inflate said packers and thereafter discharge from the tool.

'13. A treating tool for wells including a body, a pair of spaced packers thereon, a discharge section between said packers, an operating pipe to manipulate said tool and to supply liquid under pressure to be discharged into the well from said section, means operable so that the pressure liquid will iirst inflate said packers and thereafter discharge from the tool, and additional means operable by said pipe while said packers are set to divert the liquid into the bore above the tool.

$0 to--said tool, means to first direct the liquid to inilate said packers and -to thereafter eii'ect discharge oi' the liquid between the packers into the well bore, and additional means operable by relative .movement of the pipe to divert the liquid into the well bore above the packers.

PHILIP J. LEHNHARD, Jl. 

